In recent years, the demand for the organic light-emitting diode (OLED) display technology is increasing. Especially, the application to small-sized flexible curved screens and large-sized display devices such as curved televisions gains more and more attention in the display industry.
Compared with other displays, the OLED display devices have advantages of self-luminance, full-color display, wide viewing angle, high brightness, high contrast, low power consumption, etc., and thus have a broad market. However, the related art has a problem that the conventional 2T1C (i.e., 2 transistors and 1 capacitor) pixel driving circuit only converts a voltage signal into a current signal simply, without taking the problem of fluctuation of a turn-on voltage caused by the process fluctuation during the manufacturing process of the transistor into consideration. As a result, the problem of image quality, such as obvious spots and Mura (i.e., uneven brightness), of a display picture of the OLED display device occurs, and the display quality of the products is affected.